1. Field of the Invention
The present invention relates to an X-ray fluorescence spectrometer of a type wherein analysis is performed by transporting a sample to be spectroscopically analyzed towards an irradiating position and positioning a target area of the transported sample at the irradiating position.
2. Description of the Prior Art
For example, the X-ray fluorescence spectrometer has been well known in the art, in which a sample mounted on a sample holder and placed on a turret together with the sample holder is transported from a delivery position, at which replacement of the sample holder is carried out, towards an rxcex8 stage at an irradiating position where the sample is irradiated with primary X-rays, by rotation of the turret and an arbitrarily chosen minute portion of an area to be measured of the sample is analyzed after the area to be analyzed of the sample has been positioned by appropriately driving the rxcex8 stage at the irradiating position. With this type of the X-ray fluorescence spectrometer, it is possible to implement a mapping analysis (a distribution analysis) by repeating positioning and measurement to analyze a plurality of minute portions. Conversely, if averaged data are desired to be secured while a problem associated with non-uniformity of the sample is avoided, it is possible to achieve analysis of a round-shaped or ring-shaped target area by utilizing a so-called spinning function to continuously rotate the rxcex8 stage at the irradiating position during measurement.
However, separate from a rotary turret that is a transport means, there is employed an rxcex8 stage that is a positioning means. In other words, since the rotary turret that performs a transport function for transporting the sample, the r stage that performs a positioning function for positioning the target area in an r direction and the xcex8 stage that performs a positioning function for positioning the target area in a xcex8 direction are separately employed, the spectrometer is bulky and complicated in structure, resulting in increase of the cost.
Accordingly, the present invention has been devised with a view to the foregoing problems and is intended to provide an improved X-ray fluorescence spectrometer of a simplified structure of the type wherein analysis can be performed by transporting a sample to be spectroscopically analyzed towards an irradiating position and positioning a target area of the transported sample at the irradiating position an X-ray fluorescence spectrometer of a simplified structure of a type in which
In order to accomplish the foregoing object, the X-ray fluorescence spectrometer of the present invention includes an r drive means and a xcex8 drive means. The r drive means is operable to drive an r drive shaft to transport a sample holder in a circumferential direction about the r drive shaft between an irradiating position, at which the sample mounted in a sample holder is irradiated with the primary X-rays, and a delivery position at which replacement of the sample holder takes place and, also, for driving the r drive shaft at the irradiating position to thereby position a target area to be analyzed of the sample in the circumferential direction. The xcex8 drive means has a function of driving a xcex8 drive shaft at the irradiating position to continuously rotating the sample holder about a center axis thereof and operable to drive the xcex8 drive shaft at the irradiating position to position the target area of the sample about the center axis. The r drive shaft and the xcex8 drive shaft form a dual coaxial shaft assembly.
With the X-ray fluorescence spectrometer according to the present invention, when the r drive means drives the r drive shaft, both of the transport function of transporting the sample and the positioning function of positioning the target area in the r direction can be performed. Moreover, the xcex8 drive shaft of the xcex8 drive means performing the function of positioning the target area in the xcex8 direction and the r drive shaft of the r drive means form a dual coaxial shaft assembly. Accordingly, the spectrometer can be assembled compact in structure, resulting in reduction of the cost. Also, as is the case with the xcex8 stage employed in the conventional spectrometer, the xcex8 drive means has a spinning function of continuously rotating the sample at the irradiating position.